During the last decade, mobile telecommunications has become the predominant form of communications and further growth is expected in the years to come. Mobile telecommunications relies on the existence of a radio network providing radio coverage by means of base stations in areas through which mobile terminals can move. The base stations are connected to a core network of the telecom provider in order to allow communication services to be established. The core network comprises several further telecommunications nodes. One such a node, e.g. a Home Location Register (HLR), a Home Subscriber System (HSS) or a domain name server (DNS), is a central database with communication identifiers that are required to establish a communication service (e.g. a voice call or a data transfer) with one or more of the mobile terminals as is known in the art. The central database is part of the core network of the network provider.
The existing 3G and 4G telecommunication standards require the availability of the communication identifiers from the central database (e.g. the HLR or the HSS) to establish a communication service with the terminals in the coverage area of the base station. If the central database is not available, a communication service cannot be established. Such a situation of unavailability of the central database communication identifiers may e.g. arise when a catastrophic event occurs (e.g. an earthquake, flooding, explosion) or due to hardware or software failures in the telecommunications system. In one particular example, the connection link between one or more base stations (that as such are still able to provide radio coverage for the terminals for one or more communication services) and the core network may be broken. In one other example, the connection link with the base station is operational, but other parts of the core network do not operate appropriately such that the central database cannot be accessed.
In emergency situations, there is a need for communication in the relevant area and if the base stations are still able to provide services, this capacity is desired to be used to provide communication services. Such services may include SMS, location information provisioning (e.g. GPS coordinates), e-mail and, if possible, voice communication. However, since the central communication identifier information database is not available, the existing standards do not allow for these communication services to be established.